The present invention relates to an apparatus for cutting and, more particularly, is concerned with a method and apparatus for cutting patterns from sheet material such as cardboard, plastics, thin metal and similar sheet materials.
It is already well known to cut pattern pieces from sheet material by means of an automatically controlled cutting machine. Such patterns may be used as templets or guides in future cutting operations or for other purposes. In the garment industry, it is well known to use such patterns to lay out a marker, that is the array of patterns as they are cut from a piece or layup of fabric material.
U.S. Pat. No. 3,477,322 issued on November 11, 1969 illustrates and describes an automatically controlled cutting machine which produces two dimensional pattern pieces from a cutting program defined in a memory device, such as a magnetic tape, a punched tape or a deck of punched cards. The cutting program can also be generated "on line," that is, the cutting operation is carried out simultaneously with the marker generation process or the operation determining the shapes of the pattern pieces, for example, a pattern grading operation.
It is also known, as indicated by U.S. Pat. No. 3,495,492 issued on Feb. 17, 1970 and having the same assignee as the present application, to utilize a numerically controlled cutting machine to cut out the actual garment, upholstery or other pieces from a layup of limp fabric material in accordance with a marker that has previously been formed from a plurality of patterns.
The cutting of patterns from cardboard and the like and the cutting of the actual garment or upholstery pieces from a layup of limp sheet material has been performed in the past with different cutting tools on different cutting tables because of the different natures of the two cutting operations. In generating patterns, only a few layers of cardboard, not generally exceeding three, are cut at a single time and, therefore, a chisel-type tool such as shown in U.S. Pat. No. 3,477,322 operating against a relatively rigid surface supporting the cardboard sheet material is adequate. On the other hand, the cutting machine which cuts out the garment or upholstery pieces from a multiply layup of limp fabric sheet material utilizes a reciprocating type cutting blade and the table supporting the layup has a penetrable support bed that is penetrated by the reciprocating blade as shown and described in U.S. Pat. No. 3,495,492. Another related cutting machine with a reciprocating cutting blade is shown in U.S. Pat. No. 3,533,320 which discloses a pair of conveyors placed end to end to establish an intermediate throatway through which the reciprocating cutting blade operates while the fabric material is moved under the blade by the conveyors.
Although the cutting tools and the support beds of fabric cutting machines differ from the tool and bed used to generate patterns, much of the equipment including the control computers and carriages which translate the tools and materials relative to one another is basically the same and represents a substantial portion of the cost of the cutting machines. If a single, automatically controlled machine could be adapted to perform both operations, substantial savings would be had. Pattern cutting and layup cutting could be performed on a single machine in which the high-cost portions, that is the control computer, the basic support table and carriage drive mechanisms, are utilized in both operations.
It is, accordingly, a general object of the present invention to disclose a cutting machine which is adapted to both pattern cutting and fabric cutting operations. More particularly, it is an object of the present invention to disclose apparatus which uses the basic supporting table, control computers and drive carriages of a fabric cutting machine for cutting patterns.